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It is November 2012 and it is time to head back to Antarctica. This year we are a team of researchers and students from University of Canterbury (NZ), UC Davis (USA) and the Natural History Museum, London. We are coming from the research areas of Microbial Biodiversity, Microbial Ecology and Geobiology. We will be working in the McMurdo Dry Valleys and study the benthic biology of Lake Fryxell and Lake Vanda. In total, we will be in Antarctica seven weeks, two weeks at Lake Fryxell and three weeks at Lake Vanda, which is very exciting !

Cyanobacteria-based microbial mats and microbialites cover large parts of these lakes. The lakes are ice-covered and meromictic with a stratified water column, which makes them very interesting systems to study how environmental conditions affect microbial diversity and community composition and microbialite morphologies and their assemblages. The microbial communities will be collected by divers ( ...not me but the other members of my team). They will also characterise the different shapes of microbialite structures, as well as light conditions and photosynthesis activity of the lake environment. We will also do light microscopy to study the cyanobacterial morphotype diversity.

Although I have been writing already for several weeks about different regions and lakes in Antarctica, I have never posted a map.

Antarctica

Map of Antarctica showing the location of Ross Island with US (McMurdo ) and the NZ Antarctic (Scott Base) stations, and the Dr Valley located in Victoria Land, continental Antarctica.

Dry Valleys (Southern Victoria Land)

Map of the Dry Valleys (McMurdo Dry Valleys ASMA Manual) , showing Pearse Valley with Lake Joyce, Wright Valley with Lake Vanda and Taylor Valley with Lake Hoare, which will be the last lake that we are planning to visit. The Dry Valleys are on continental Antarctica.

The last several days, we had very windy weather, and made it impossible for our dive team to do any diving from our second dive hole that is further out on the lake. Winds out in the mountains and towards the polar plateau were far more extreme than at the lake, as we could see enormous snow plumes.

The lake floor is covered with cyanobacteria-dominated mats of different thickness. The microbial mats from 59 ft are ca 1 cm thick and have small pinnacles growing out off the flat mats. The cross-section show differently coloured layers with a brown layer on top and a green and purple layer below (the colours are difficult to see under the yellow coloured light of our science tent). The different colours are due to the production of pigments for efficient uptake of light.

At Lake Vanda we also want to explore microbial communities and the microbial structures forming within the lake. However, before we can get started with the science we had to wait for our equipment to be flown into the camp from Lake Joyce, and drill and melt a hole in the lake ice big enough for the divers to get into the water.

Lake Vanda is in the Wright Valley and a lot bigger than Lake Joyce with a length of around five km. It is also ice-covered but the ice is in average only 4 meters thick. Lake Vanda is meromictic, which means that the deeper layers never mix with the upper layers. This creates very different condition in the shallower and deeper parts of the lake, and therefore very different microbes will likely be found in the different sections of the water column.

Lake Ice

In contrast to Lake Joyce the lake ice is very smooth with millions of fine cracks and trapped bubbles, creating amazing patterns and shapes.

After one week at Lake Joyce it was time to pack and move our entire camp to Lake Vanda. Although i only stayed one week at Lake Joyce the rest of the team had spend close to a month there. It took two days to pack and four days to move all of the team and the equipment to Lake Vanda. This was also partly due to strong winds, which stopped the helicopter traffic.

Packing Lake Joyce camp

Lake Vanda is also an ice-covered lake of the Dry Valleys and located in the Wright Valley. In order to get there we flow over the Asgard Range with amazing views over glaciers and mountain peaks.